Account for all listener adding/removing situations and for the subtype problem (#1)

Author: JordanMartinez

.github/workflows/ci.yml

@@ -1,53 +1,66 @@
 name: CI
 
-# Run CI when a PR is opened against the branch `main`
-# and when one pushes a commit to `main`.
+# Run CI when a PR is opened against the branch `master`
+# and when one pushes a commit to `master`.
 on:
   push:
     branches: [master]
   pull_request:
     branches: [master]
 
+# Run CI on all 3 latest OSes
 jobs:
   build:
-    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
 
-      - uses: purescript-contrib/setup-purescript@main
+      - name: Set up Node toolchain
+        uses: actions/setup-node@v3
         with:
-          purescript: "0.15.7"
-          purs-tidy: "0.9.2"
-          psa: "0.8.2"
-          spago: "0.20.9"
-          psa: "0.7.2"
+          node-version: "16"
+
+      - name: Cache NPM dependencies
+        uses: actions/cache@v3
+        env:
+          cache-name: cache-node-modules
+        with:
+          path: ~/.npm
+          key: ${{ runner.os }}-build-${{ env.cache-name }}-${{ hashFiles('**/package.json') }}
+          restore-keys: |
+            ${{ runner.os }}-build-${{ env.cache-name }}-
+            ${{ runner.os }}-build-
+            ${{ runner.os }}-
+
+      - name: Setup PureScript tooling
+        run:
+          npm i -g purescript@latest purs-tidy@latest purescript-psa@latest spago@latest
 
       - name: Cache PureScript dependencies
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         with:
           key: ${{ runner.os }}-spago-${{ hashFiles('**/*.dhall') }}
           path: |
             .spago
             output
 
-      - name: Set up Node toolchain
-        uses: actions/setup-node@v2
-        with:
-          node-version: "16"
-
       # Compile the library/project
       #   censor-lib: ignore warnings emitted by dependencies
       #   strict: convert warnings into errors
       # Note: `purs-args` actually forwards these args to `psa`
       - name: Build the project
         run: |
-          spago build --purs-args "--censor-lib --strict"
+          npx spago build --purs-args "--censor-lib --strict"
 
       - name: Run tests
         run: |
-          spago test
+          npx spago -x test.dhall test
 
       - name: Check Formatting
+        if: runner.os == 'Linux'
         run: |
           purs-tidy check src test

.gitignore

@@ -8,3 +8,4 @@
 /.purs*
 /.psa*
 /.spago
+/.vscode

spago.dhall

@@ -1,10 +1,10 @@
 { name = "node-event-emitters"
 , dependencies =
   [ "effect"
+  , "either"
   , "functions"
   , "prelude"
-  , "safe-coerce"
-  , "unsafe-coerce"
+  , "unsafe-coerce" 
   ]
 , packages = ./packages.dhall
 , sources = [ "src/**/*.purs" ]

src/Node/EventEmitter.js

@@ -1,35 +1,24 @@
-import events from "node:events";
+import EventEmitter from "node:events";
 
 const newImpl = function () {
-  return new events.EventEmitter();
+  return new EventEmitter();
 }
 export { newImpl as new };
 
-export function listenersLengthImpl(emitter, event) {
-  return emitter.listeners(event).length;
-}
-
-export function setMaxListenersImpl(emitter, max) {
-  emitter.setMaxListeners(max);
-}
-
-export function onImpl(emitter, eventName, cb) {
-  emitter.on(eventName, cb);
-  return cb;
-}
+// addEventListener - not implemented; alias to `on`
+export const unsafeEmitFn = (emitter) => emitter.emit.bind(emitter);
+export const eventNamesImpl = (emitter) => emitter.eventNames();
+export const symbolOrStr = (left, right, sym) => typeof sym == "symbol" ? left(sym) : right(sym);
+export const getMaxListenersImpl = (emitter) => emitter.getMaxListeners();
+export const listenerCountImpl = (emitter, eventName) => emitter.listenerCount(eventName);
+// listeners - not implemented; returned functions cannot be used in type-safe way.
+export const unsafeOff = (emitter, eventName, cb) => emitter.off(eventName, cb);
+export const unsafeOn = (emitter, eventName, cb) => emitter.on(eventName, cb);
+export const unsafeOnce = (emitter, eventName, cb) => emitter.once(eventName, cb);
+export const unsafePrependListener = (emitter, eventName, cb) => emitter.prependListener(eventName, cb);
+export const unsafePrependOnceListener = (emitter, eventName, cb) => emitter.prependOnceListener(eventName, cb);
+// removeAllListeners - not implemented; bad practice
+// removeEventListener - not implemented; alias to `off`
+export const setMaxListenersImpl = (emitter, max) => emitter.setMaxListeners(max);
+// rawListeners - not implemented; returned functions cannot be used in type-safe way.
 
-export function offImpl(emitter, eventName, cb) {
-  emitter.off(eventName, cb);
-}
-
-export function onceEventListener(emitter, eventName, cb) {
-  emitter.once(eventName, cb);
-}
-
-export function emitImpl(emitter, eventName) {
-  return function (a1, a2, a3, a4, a5, a6, a7, a8, a9, a10) {
-    emitter.emit(eventName, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10)
-  };
-}
-const undefined_ = undefined
-export { undefined_ as undefined }